1. Field of the Invention
The invention relates to a tool for machining workpieces having a parent body which can be expanded at least in selected zones thereof, having at least one geometrically defined outer cutting edge projecting beyond a circumferential surface of the tool, and having a setting device that sets the radial distance of the cutting edge from the center axis of the tool.
2. Related Art
Tools of this type are known. They serve to remove chips from a workpiece by means of a cutting edge, for example during the surface machining of bores. As a rule, the tool is set in rotation in order to produce a relative movement between the cutting edge and the workpiece surface to be machined and in order to remove chips. However, it is also possible to set the workpiece in rotation and to clamp the tool in a rotationally fixed position.
Tools which have a setting device, by means of which the position of the circumferential cutting edge of the tool can be set relative to its center axis, are also known. The known tools may have, for example, rings of cutting edges, but also, for example, may be monoblock tools. In each case, the setting device has a setting element which is designed as a cone and is part of a wedge mechanism. By displacement of the cone, the ring of cutting edges or the parent body of the monoblock tool can be expanded to a greater or lesser extent in order to vary the position of the cutting edge. For adjusting the cutting edge, the cone is displaced in the direction along the center axis of the tool and interacts with an inner conical surface of the ring of cutting edges or of the tool. There are high frictional forces between the surface and the cone, so that fine adjustment of the cone is often not possible. As a result, it is often not possible to realize an exact setting, or it is possible only at an increased production cost. Furthermore, high setting forces are required in order to set the position of the cone. It has also been found that a displacement of the cutting edge is not reversible in many cases.